RE: Counting Elements in a List
- To: mathgroup at smc.vnet.net
- Subject: [mg27969] RE: [mg27959] Counting Elements in a List
- From: "Harvey P. Dale" <hpd1 at nyu.edu>
- Date: Tue, 27 Mar 2001 01:26:06 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
John: Count[Transpose[mylist][[4]], x_/;x>3] Best, Harvey Professor Harvey P. Dale Director National Center on Philanthropy and the Law New York University School of Law Room 206A 110 West 3rd Street New York, N.Y. 10012-1074 -----Original Message----- From: JOHN C ERB [mailto:JOHN_C_ERB at prodigy.net] To: mathgroup at smc.vnet.net Sent: Monday, March 26, 2001 5:27 AM To: mathgroup at smc.vnet.net Subject: [mg27959] Counting Elements in a List I have a list in which I want to count the number of times the 4th element (i.e., 4th column) meets certain specifications (e.g., where it greater than or equal to 8). I can do this by: mylist = {{1, 2, 3, 4}, {1, 2, 3, 5}, {1, 3, 4, 6}, {1, 3, 6, 9}, {2, 4, 7, 8}}; Length[Select[mylist, #[[4]] >= 8 &]] Surely, there is another, more direct, way of doing this using Count? Thank you, John C. Erb email: John_C_Erb at prodigy.net